Thanks for your fast answer!

some good aproaches but no hit...

pos() doesn't work because if the string only contains a prefix of the given expression (what will be the hot case I'm looking for) I will get undef and not the position I need or do I overlook sth. here?

My "window" can become as large as it likes, doesn't matter, but I have to ensure that no matching will be overseen, that's quite important! It's just to make the searching faster and if I know that the first n characters can be thrown away because they can never be part of a matching would do the job. Any alternative suggestion?

In reply to Re^2: Find Prefix if regex didn't match by demoralizer
in thread Find Prefix if regex didn't match by demoralizer

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